Booked a trip for 5 thru expedia need to change 1 ticket, can I book a 1way and he

[curranskog]

is a no show for original? expedia says if booked together if 1 changes they all do at $150 per ticket plus cost of flight difference of each. I was hoping to get around it by just booking a one way for the day before and him just being ano show-can I do this if I tell them when I check in that he couldn't make the flight? with no other problems?